ucar.unidata.io

Class RemoteRandomAccessFile

java.lang.Object

ucar.unidata.io.RandomAccessFile

ucar.unidata.io.RemoteRandomAccessFile

All Implemented Interfaces:

java.io.Closeable, java.io.DataInput, java.io.DataOutput, java.lang.AutoCloseable, FileCacheable, ReadableRemoteFile

Direct Known Subclasses:

HTTPRandomAccessFile, S3RandomAccessFile

public abstract class RemoteRandomAccessFile
extends RandomAccessFile
implements ReadableRemoteFile

An abstract superclass for remote RandomAccessFile

Field Summary

Fields

Modifier and Type	Field and Description
protected static long	defaultMaxReadCacheSize
protected static int	defaultRemoteFileBufferSize
protected static int	defaultRemoteFileTimeout
protected java.lang.String	url

Fields inherited from class ucar.unidata.io.RandomAccessFile

allFiles, BIG_ENDIAN, bigEndian, buffer, bufferModified, bufferStart, dataEnd, dataSize, debugAccess, debugLeaks, defaultBufferSize, endOfFile, file, fileChannel, filePosition, LITTLE_ENDIAN, location, openFiles, readonly, showOpen, showRead

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	RemoteRandomAccessFile(java.lang.String url, int bufferSize, long maxRemoteCacheSize)

Method Summary

Modifier and Type	Method and Description
void	close() Close the file, and release any associated system resources.
protected int	read_(long pos, byte[] buff, int offset, int len) Read data into the buffer, and return number of bytes read.
long	readToByteChannel(java.nio.channels.WritableByteChannel dest, long offset, long nbytes) Read nbytes bytes, at the specified file offset, send to a WritableByteChannel.

Methods inherited from class ucar.unidata.io.RandomAccessFile

acquire, acquire, eject, enableDefaultGlobalFileCache, flush, getAllFiles, getBufferSize, getDebugLeaks, getDebugNbytes, getDebugNseeks, getFilePointer, getGlobalFileCache, getLastModified, getLocation, getMaxOpenFileCount, getOpenFileCount, getOpenFiles, getRandomAccessFile, isAtEndOfFile, isDirectory, length, order, order, reacquire, read, read, read, readBoolean, readBuffer, readByte, readBytes, readBytes, readChar, readDouble, readDouble, readFloat, readFloat, readFully, readFully, readInt, readInt, readIntUnbuffered, readLine, readLine, readLong, readLong, readShort, readShort, readString, readString, readStringMax, readStringMax, readUnsignedByte, readUnsignedShort, readUTF, release, searchForward, seek, setBufferSize, setDebugAccess, setDebugLeaks, setExtendMode, setFileCache, setGlobalFileCache, setMinLength, shutdown, skipBytes, skipBytes, toString, unread, write, write, write, writeBoolean, writeBoolean, writeByte, writeBytes, writeBytes, writeBytes, writeChar, writeChar, writeChar, writeChar, writeChar, writeChar, writeChars, writeChars, writeChars, writeDouble, writeDouble, writeDouble, writeDouble, writeDouble, writeDouble, writeFloat, writeFloat, writeFloat, writeFloat, writeFloat, writeFloat, writeInt, writeInt, writeInt, writeInt, writeInt, writeInt, writeLong, writeLong, writeLong, writeLong, writeLong, writeLong, writeShort, writeShort, writeShort, writeShort, writeShort, writeShort, writeUTF

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface ucar.unidata.io.ReadableRemoteFile

closeRemote, readRemote

Field Detail

defaultMaxReadCacheSize

protected static final long defaultMaxReadCacheSize

See Also:

Constant Field Values

defaultRemoteFileBufferSize

protected static final int defaultRemoteFileBufferSize

See Also:

Constant Field Values

defaultRemoteFileTimeout

protected static final int defaultRemoteFileTimeout

See Also:

Constant Field Values

url

protected final java.lang.String url

Constructor Detail

RemoteRandomAccessFile

protected RemoteRandomAccessFile(java.lang.String url,
                                 int bufferSize,
                                 long maxRemoteCacheSize)

Method Detail

read_

protected int read_(long pos,
                    byte[] buff,
                    int offset,
                    int len)
             throws java.io.IOException

Read data into the buffer, and return number of bytes read. If the read cache is enabled, the cache will be checked for data first. If not in the cache, data will be read directly from the remote service and placed in the cache. All reading goes through here or readToByteChannel;

Overrides:

read_ in class RandomAccessFile

Parameters:

pos - start here in the file

buff - put data into this buffer

offset - buffer offset

len - this number of bytes

Returns:

actual number of bytes read

Throws:

java.io.IOException - on io error

readToByteChannel

public long readToByteChannel(java.nio.channels.WritableByteChannel dest,
                              long offset,
                              long nbytes)
                       throws java.io.IOException

Description copied from class: RandomAccessFile

Read nbytes bytes, at the specified file offset, send to a WritableByteChannel. This will block until all bytes are read. This uses the underlying file channel directly, bypassing all user buffers.

Overrides:

readToByteChannel in class RandomAccessFile

Parameters:

dest - write to this WritableByteChannel.

offset - the offset in the file where copying will start.

nbytes - the number of bytes to read.

Returns:

the actual number of bytes read and transfered

Throws:

java.io.IOException - if an I/O error occurs.

close

public void close()
           throws java.io.IOException

Description copied from class: RandomAccessFile

Close the file, and release any associated system resources.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Specified by:

close in interface FileCacheable

Overrides:

close in class RandomAccessFile

Throws:

java.io.IOException - if an I/O error occurrs.